Through over-use, traumatic events and/or debilitating disease, a person's joint may become damaged to the point that the joint is repaired. One type of procedure to address damage to a person's joint is an arthroplasty procedure. Arthroplasty is a medical procedure where a joint of a patient is replaced, remodeled, or realigned. Damage to the joint may result in a reduction or wearing away of cartilage in the joint area, which operates to provide frictional, compressive, shear, and tensile cushioning within the joint. As such, reduction in cartilage in a joint causes pain and decreased mobility of the joint. To combat this joint pain, a patient may undergo the arthroplasty procedure to restore function and use of the damaged joint.
One type of arthroplasty procedure is known as Total Knee Arthroplasty (TKA). In general, TKA involves replacing the diseased or damaged portion of the knee with metal or plastic components that are shaped to approximate the replaced portion or shaped to allow movement of the joint and relieve the joint pain. Thus, a TKA procedure may include replacement of a portion of the femur and a portion of the tibia that make up the knee joint. Similar procedures may be performed on other damaged joints, such as a hip, a shoulder, an elbow, and the like. General discussion of arthroplasty procedures herein are directed specifically to TKA-type procedures, but may be applied to arthroplasty procedures of other types of joints.
In a TKA procedure, a damaged portion of the femur is cut off and replaced with a metal or plastic component that is shaped to mirror or approximate the replaced portion. The metal or plastic component may be impacted onto the femur or fixed using a type of surgical cement or other fastening system. Further, a damaged portion of the tibia may also be removed and replaced with a generally flat metal or plastic component that is shaped to mirror or approximate the replaced portion. The tibia replacement implant may also be attached to the tibia through impaction onto the bone or fixed using a type of cement. In essence, the damaged knee joint is replaced with a prosthetic knee. In general, the femur implant and the tibia implant are mated to form a prosthetic joint that approximates the shape and operation of the replaced knee joint. In some examples, a plastic surface is placed between the femur implant and the tibia implant to prevent metal-on-metal interaction between the implants during use of the replaced joint.
As mentioned above, a TKA procedure often involves the removal and replacement of portions of the femur and/or tibia of the injured knee. During the removal, the portions of the femur and tibia may be cut, drilled, resurfaced, and the like to create a surface on the bones that mates with the respective implants. In one particular example, the ends of the bones (distal end of the femur and proximal end of the tibia) may be completely removed to create generally flat surfaces to which the implants are mated. Once the mating surfaces for the implants are created on the receiving bones, the implants may then be attached to the bones as described above.
Although the broad outline of the TKA procedures is described above, there is much to consider when performing the procedure. For example, patients may undergo a preoperative planning phase including one or more consultations with a doctor a month or more before the TKA is performed. In addition, alignment of the implants in the joint with the rest of the patient's anatomy is crucial to the longevity of the implant and the implant's effectiveness in counteracting the pre-TKA joint condition. As such, systems and methods have been developed to produce customized arthroplasty cutting jigs that allow a surgeon to quickly and accurately perform the necessary resections of the bones that result in a successful TKA procedure. In particular, cutting jigs may be generally customized for the particular patient's joint undergoing the TKA procedure to ensure that the implants align with the patient's anatomy post-procedure. Through the use of such customized cutting jigs, the TKA procedure is both more accurate (ensuring more longevity to the implants) and quicker (reducing the time required for the surgical procedure, thereby reducing the potential for post-surgery complications).
In general, cutting guides or cutting jigs used in TKA procedures may attach to one or more bones of the knee and provide a cut line to the surgeon for use during the TKA surgery. In particular, a femur cutting jig may attach to the distal end of the femur and include a cut guide or line. A surgeon, during the procedure, inserts a saw device into or through the cut line to resect the distal end of the femur. Similarly, a tibia cutting jig may attach to the proximal end of the tibia and include a cut line that the surgeon uses to resect the proximal end of the tibia. In this manner, the ends of the femur and tibia are resected by the surgeon during the TKA procedure, thereby creating a smooth mating surface for the implants. As should be appreciated, the location and angle of the cut plane through the respective bone surface indicated by the cutting jig may determine the overall effectiveness of the TKA procedure. As such, a cutting jig utilized during the procedure should be designed to provide the proper location and orientation of the cut plane on the bones of the affected joint such that treatment of the region can be performed accurately, safely, and quickly.
Conventional jigs may be complicated to create, suffer from inaccuracies, overly time consuming to generate, overly expensive to generate, and many other concerns. Thus, while such systems may be useful, there are numerous opportunities to advance the art. It is with these and other issues in mind, among others, that various aspects of the present disclosure were developed.